Merge bitcoin-core/secp256k1#1383: util: remove unused checked_realloc

b097a46 util: remove unused checked_realloc (Cory Fields)

Pull request description:

  Usage was removed in 6fe5043 . This should be a NOOP.

  Noticed when analyzing for zenbleed exposure: stdlib calls that aren't optimized away.

  In this case realloc isn't making it into the final binary, but as far as I can tell this is completely dead code and should be dropped.

ACKs for top commit:
  jonasnick:
    ACK b097a46
  real-or-random:
    ACK b097a46

Tree-SHA512: d4249215eddd4035be2b50a8bb48b8a681abdab4ab41ca53f6c2a2507edfbc9ffa39ba22eb48e7da52f978e224198294495ce64f9d571d98c19283b20b82a63a

src/util.h

@@ -152,14 +152,6 @@ static SECP256K1_INLINE void *checked_malloc(const secp256k1_callback* cb, size_
     return ret;
 }
 
-static SECP256K1_INLINE void *checked_realloc(const secp256k1_callback* cb, void *ptr, size_t size) {
-    void *ret = realloc(ptr, size);
-    if (ret == NULL) {
-        secp256k1_callback_call(cb, "Out of memory");
-    }
-    return ret;
-}
-
 #if defined(__BIGGEST_ALIGNMENT__)
 #define ALIGNMENT __BIGGEST_ALIGNMENT__
 #else